Elbow-making machine



Dec. 19,- 1922. 1,439,559. I A. D. KUMPF. u

ELBOW MAKING MACHINE.

FILED `SEF"I.24. 192i. 4 SHEETS-SHEET l.

ATTORNEY Dec. 19, 1922. 1,439,559. A I A. D. KUMPF. y

ELBOW MAKING MACHINE. Y

FILED SEP`24, 192|. I 4 SHEETS-.SHEET 2.4

INVENTOR ATTORNEY WITNESS Dec, 19, 1922. 1,439,559.

A. D. KUMPF.

ELBOW MAKING MACHINE.

FILED SEPT-24, |921. 4 SHEETS-SHEET 3.

F. n? s 41 26 "3. y @i l' .f/f .v1/fm- 3f .9.9 a# v 2,2%; 100 v /AX uyustDJumpf INVENTOR ATTORNEY Dec. 19,1922.

1,439,559. A. D. KUMPF.v ELBOW MAKING MACHINE.

FILED SEFL24, 192.1. 4 SHEETS-SHEET 4.

90 42 f/w//// lf ATTORNEY Patented Bee. i9. i922.

efT-frifif AUG-UST f I). KUMPF., PHILADELPHIA, SYLVANX.

ELBOW-MAKING Mii-'onine'.

chin'e Eof 'the type referred 'to ivhieh is Chin'- eetei'ized hy zi novel inea-ns iei'.pii1na'i'ily y ended ereuite grooves voi ribs in straight. ftLc-iilei' sections, each iii'oove mi itil; 'fleeing Subsequently creased oi i lded em'nin'eeeion Simultaneously with the feed.V ier-italici of the tube 'iezicly for the formi-ng oiI the succeeding groove o1' and the pro- (lneiio'n ete'p hy step of the 'desired elbow sciiti on.'

inotl r'ol'iject oi this invention is rkthe ptoi'isiion el fa mech-ine for lioiniing Vmetal ellin v lnilzi gtecti'cns cliiiiectei'ixed"by the feet that the veen.. ng m' ieli-linf.;icipeizitio'n lproper ies-iiiltf; in ltlie ep b v etepeccni'zite productif-in of? Athe ieqiiisite ein"` nfe in the elbow.

A. 'lnithei object is tto provide si novel stencil-:life et inncliine foi melting el'ieet metal ellionzelontolt, oi.' vfrom, straight tnlmlzii seciimie which mie not seemed until eit-e'i'tthe ell'ieiv formingopci'zition is (oinpletel. I

A Still "lnifi'her object of this invention is to piiovide 'mi elbow infikingoi' forming; ine.h chine l'ee'mprising yinit *few ope'i'ziting 'parte which will fashion o1' shape en elbow zindeifeet the creasing* operation in a simple end eniiemel'y ellieient ni'annei und Lthereby produce e comparatively 'smooth 'and attraetivelv iiniehed eiticle.

'Feet-lier objects of Atl Y invention' a'i'e to Simplify, facilitate and clielaipen the mennintnie ol: Sheet vmetal -elloows *i'oni' Seamless "acts in tei more from ecnnefd or Sea'inlese etllnfig-jlit tn! Application led 'Septembei 24, 1921. Seiiifa 502,933;

reference is i'to he 'had to` the accompanying A sheets d attinge cenftilttine; a part of thie speciliezttion.':and 'in' ivliihllike 'characters-oi ti ference qnete th'eisa'me or coifrespondingpints iii ll 'the views.

making jnnicliineKA embodying the lessentiel ieetineeoii this invention.

Fig. is e central l'ongitiidin'al eind ver`A tical Section thiongh the elboivmz'iking machine 'with pzi'its in oni/Side elevation for the cleziinees.

ie en enlarged ld'eta'il view of eef! Fig'. 4 is e longitiidinal side Yeleviition oil tionzil vie-iv 'of 'the`ci'eziselfolini'ng und `finisllii lligyl) Siezicoiresponding fece view :it 'the "FiglOis ziiriignenta'ry Side view of sin elhe'iv :is vproduced 'my machine, ADut being' breken nivey oi jiny 'section for the salie K :is .hereinafter more fully described. y d

il? is la Sectioiion the fli'ne 1.2-1.2 in the iiveceding; "ligure eind lookingfto the nie.' n i5 is'en yenle'ckeed deteil vieee view oi ciienlly explained. y

i6 is :i similar detail ieee view o'l'the @nier forming-fdisk and later on 'particularly deeciibedgend.'

Fig. 1T- is en edge vien' ehoiving in aggerated thickness the peripheral edge formation of the forming-disks referred to by the two preceding figures.

According to the embodiment of the invention yshown l providey a. base conveniently-though not essentially-of rectangular configuration and adapted for clamping xture wherever desired, said base 20 having secured thereon' a pair of parallel disposed standards. 2l fashioned to constitute journals or bearings for the drive shaft 22. :This drive shaft may be rotated manually or power driven-as shown-by means of a pulley 23 and belt 24 from any convenient and suitable source.r mounted on, or formed integral with, the aforesaid base 20, are a pair of spaced bearings 25, 26, disposed at right angles to the axis of the before mentioned standards 2l, said latter bearings 25, 26, housing a tubular mandrel 27 which is plugged at each end by blocks 2S and 28. llt is to be here noted that the tubular mandrel 27 is rigidly held within the bearing 25 whilst the opposed end thereof is shrouded with a thin annular sleeve 29--the purpose and function whereof will be later on explained-and axially supported in the bore 30 ofthe bearing 26 to provide an entry clearance 3l for the tubu-y lar section to be subsequently formed into an elbow. v

Longitudinally of the aforesaid tubular mandrel 27 is a shaft 32 which is journaledl in the blocks 28 eccentric to the longitudinal axis of said mandrel 27, and this shaft 32 is adapted for intermittent'rotation by means of a bevel gear 33 on the outer end thereof meshing at intervals with the toothed portion of a mutilated or interrupted gearwheel 34 securely keyed on the drive shaft 22. Formed integral with or rigidly secured in the forward end of the shaft 32 is a crank pin 35 that serves in use tov actuate or move a-forming-disk 36-Figures 6, 7, 8

and 9-arcuately eccentric relative to a fixed.

point or stud 37 conveniently threaded into the outer end of the plug block 28 in the mandrel 27, whilst at the same time allowing of its displacement dianietrically in a plane taken centrally through .the said cranh pin 35 and centrally through said stud 37, but at right angles to their axes. A* the same time this crank pin 35 serves also to oscillate a second forming-disk 33 pivoted on the stud 37 in superficial abutment with the forming-disk 36 from the right to the left hand, andA vice versa, as hereafter fully explained. The movements of these formingdisks 36, 38, effect the primary expansion of the metal tubular section outwardly into and between the arcuate flared portion 39 of an annular die and creasing collar 40 and the ropposed correspondingly flared outer part 41 of the aforesaid bore 30 in the bearing 26 to inverted V-shaped cross section as shown ySimilarly y atthe broken fragmentary part 42 in Figure l0, said expanded part 42 extending sub-V stantially around three-quartersof the circumference of the tubular section. It is also to be particularly noted that this outwardly expanded iff-shaped part or bead 42 is of a maximum depth at the high point 43-Figure 6-of the opposed fiarings 36 and 4l, gradually and uniformly diminishing away to the lowermost parts of said expansion; in other words, the lower partyof the tubular section being elbowed remains undisturbed and of its natural shape as between the low points 44-li`igure lO-of the V-shaped expansion or outwardly bulged bead 42, the same being readily understood by those acquainted with the art to which this invention .appertains `:The annular die and creasing collar 40 as will be best seen from Figures l0, ll and l2, in addition to having the arcuate flaring 39 is formed with an arcuate rib or internal bead 45 similarly extending around substantially three-quarters of its bore and intermediate the inner and outer faces of said die or collar, the frontal part 46 being fashioned to a concave or moulded cross-section. In order to permit of this die or collar 40 having an outward and upward-or slight swinging-movement imparted thereto to eiect the creasing as well as the step-by-step elbow forming operations, it is formed integral with or rigidly attached by studs 47 to atransverse bar 4S provided with pintles 49 atA its ends which are journaled in angle bearings 50 securely` clamped by studs 5l. to the upper part of the hereinbefore referred to bearing 26. To effect the aforesaidup and down or rocking of the annular die and creasing collar 40 l preferably secure a removable and adjustable bar 52 transversely on the base 20 in front of the bearing 26, and on this bar 52 is pivote-d at what may be termed a locking lever 54 fashioned with a nose portion 55 adapted to contact with or normally be in engagement against the lower frontal and outer portion of said die and collar 40 as will be clearly understood on an examination of Figures l, 2, 4 and 5, of the drawings more particularly. Suitably piv oted by a shouldered pin 5G on the free end of the locking lever 54 a rod or pitman 57 having an elongated and flattened end 5S, slotted at igures .l and 3h-over the drive shaft 22 and carrying a laterally projccting antifriction roller G0 that traverses thc groove (il of an internal cam (552. keyed or otherwise fixed on the aforesaid drive shaft 22. lt is also to be noted that the groove Si of the internal cam G2 is indented at {33--l-`igure 3-for the purpose .later on explained, and it will be readily understood that rotation of the internaly cam 62 will effect the eccentric.reciprocation of the rod or pitman 57 and thereby the lateral movement 'of the llocking lever 54. As'an additional precaution against accidental -displacement 01"" the annular die and creasing collar 41 guide pins 64-mayfbe securedfin the front of the bearing 26jifor copper-ation in slots in said-die 40.

Referring Qagain t0 fthe hereinbefore Ementioned forming-disks 36, 38 and more particularly to kliligures 15, 16 and 17, it is /to ybe observed that the .forming-dislrBG lis oi' circular disk `formation and provided `with `up'- per and lower diametricallyaligning slots 66, 67, respectively, and @apertures 68; whereas the formingndisk38 is of like size and provided @with apertures 69 of like size to 'those 'designated 68, -an velongated upper slot 70,-a pivot'hole 71 and a segmental-cut awa-y lower part 72. lt iis also'to vbenoted that the peripheral 'edge of both forming disks are hyperbolically urounded `orf ,las shown at '73 fin Figure 17. ln assembling these forming-disks 36, 38, the former36--- for example-is firstly placed fwith its lower slot 67 over the fiiXedstud`37 and its upperslot 66 over the `ciankpin 35, whereupon the other `ormingdisk -38 is similarly placed by the pivot hole 7l on said `stud 37 audits 'elongated slot v7() 'on the crank pin 35. Now assuming the crank pin 35 isf-'as `ated upon.

ln order to limit and control the lateral movements 'of the formingsdisks 36, `38, as well as to maintain them 'in close 'working and non-bindingrelation, l employ a .clamp-V ing die or collar 74 as shown'to an enlarged scale in Figures 6, 13 and 14, said clamping die or Collar 74 Ahaving a relatively large eccentric bore 75 to provide aclearance for the end or' the crank pin 35,*a counter bore 76 which is screw-threaded at y77 for connection on Vthe hereinbefore referred to fixed stud'37 whereby it can beaecurately adjusted relative 'to the forming-'disk 38, after which it is rigidly retained by means or' a washer and lock nut 7 8. Spaced holes 79 are also formed `through the clamping die or collar 74 -orthe passage oi ilisterheaded pins 8O which traverse theapertures 69, 68 in the Jforming-disks 38, 36, and are screw-threaded into the plug block 28', said ilister-headed pins 80 aroviding vthe'limiting means for the lateral'i'novements of the termingdisks 38, 36 above referred to. 'lt is also to be here ncted'that the lower vpart oi the clamping die or collar 74 is roundec off at 81 for a purpose later onexplained whilst the 'inner 'face is slightly recessed to provide an annular bearing or working sur" face 82 whereby friction is reduced to a minimum between said collar `74 and the adjoining forming-disk 38.

Secured-at theback of the bearing`26 bye cap screwor the like 83 is a longitudinal bar 84 which serves to support and hold down the ljoint of a seamless or split tubuiar'section when being operated upon, said bar 84 being mounted in spaced relation over the tubular mandrel 27 and extending substanti'allythe 'full length thereof.

vThe feeding forward of the tubularsection step-by-step is accomplished by the mechanism now to be described andwhich consists of an annular yokeor thrust collar 85 Ahaving a working iton the tubular mandrel and being annularly grooved at 86 for the insertion and abutmenttherein of the inner end of the tubular section, said collar 85 also .being holed or slotted'at 87 for its free passage along the longitudinal bar 84. integral with ror securelyv fixed to the thrust collar 85 4is a 'rack bar 88 vhaving teeth 89 in number equal to the maximum number ot' creasings S30-Figure 10-required in an elbow 91 of the desired angular coniiguration. The intermittent 'feeding forward of the rack bark `88 is effected bymeans of a graaiityA ifall pawl 92 secured to a hinge pin'93 journaled in a straddle yoke 94 pivotally mountf ed at k95 on the bearing 25, Journaled on stud bolts or'other appropriate pivots y96rd: each side ot the straddle yoke 94 is the connecting rod 97 of a strap eccentric 98 mount ed or securely fixed to tle drive shaft 22 whereby it will be clearly seen that said strap leccentrics 98 eiiect the hirward forcing 'of the rack bar 88 andthrust collar 85 through ythe mechanism just'described.

Having described in detail the structure of my elbow making machine I will nowbriefly describe its operation, assuming by way of example only that it is desired to forni an elbow from a seamless straight tubular section. The annular die or creasing collar 4() occupying its normal position as shown clearly by Figure 2, and the. thrust collar being moved backwardstowards the bearing 25 to the vrequired extent, the operator forces the seamless straight tube through the n aforesaid diebr creasing collar 40 and entry clearance 31 onto and along the tubular mandrel 27 until itsinner end engages in the annular groove 86 of the thrust collar 85. lt is to be particularly observed that during the aforesaid operation'the seamless part 'of said straight tube is caused to abut or overlap longitudinally beneath the longitudinal bar 84;v The machine is now set rin operation which results through the meshing 'of the interrupted or mutilated gear 34 with the bevel gear 33 in imparting one complete revolution to the shaft 32. As hereinber'ore explained at the commencement of rotation of this shaft 32 the crank pin 35 is at its lowermost position and during the first quarter rotation of said shaft the formingdisks 36, 88, are moved over to the right hand as shown by Figure 7 causing a slight distortion or expansion of the metal between the opposed flared faces and 4l thereby commencing to form the V-shaped out wardly directed expanded part or rib 42. As the shaft 32 continues rotating to its complete half turn as shown in Figure 8 the expanded or rib part 42 is eccentrically increased to its maximum expansion by the forming-disks 36, 38, being traveled as hereinbefore set forth. Continued rotation of the shaft 32 in a contra-clockwise direction as indicated by the arrows on Figures 7 8 and 9 to the three-quarter `turn position moves the forming-disks to the position illustrated by the latter figure with a grad-y ually diminishing eccentricity in the continued formation of the expanded part or rib 42. From this latter position to the initial position the forming-disks 36, 38 are retracted eccentrically inwards with the iinishing of the part or rib 42 on the left-hand side thereof, and as said disks 86,88 regrister with the adjoining end of the mandrel 27, thek toothed portion ofthe interrupted or mutilated gear 34 leaves the bevel gear 38 and further rotation of the shaft 82, stops for an interval of time. instantly the disconnection of the gears 84. 33 takes place the rod or pitman 57 is sharply moved forward by the internal cam 82 which moves the locking lever 54 outwards away from the annular die or creasing collar 40, said movement being instantly followed by the strap eccentrics 98 through the connecting rods 97 rocking the straddle yoke 94 forward on its pivots 95. Consequent upon the forward rocking of the straddle yoke 94 the gravity fall pawl 92 forces the rack bar 88forward the distance of one tooth 89, and due to the abutment of the tubular section in the annular groove 86 of the thrust collar, a compressive force will be exerted on the tube. As a result of this forward thrust or movement of the tube the annular die or creasing collar 40 will be initially swung outwards and upwards to the dotted line position indicated by the numeral 99 on Figure which results in a raising of the lower edge of the rib or bead 45 suiiciently for the top or high point of the expanded part or rib 42 to be forced thereunden The continued forward movement of the thrust collar causes the expanded part or rib`42 to be folded over on to the surface of the pipe under the compression of the arcuate bead or rib 45 of the annular die or creasing collar 40 as will be readily understood by those acquainted with the art to which this invention appertains. It will be clearly understood that the foregoing operation takes place during the forward movement of the strap eccentrics 98 and internal cam 62 and that during their return stroke the straddle yoke 94 will be retracted and thereby move the gravity fall pawl 92 into engagement with the next succeeding tooth 89 of the rack bar 88. The machine will now be in position to commence the forming of the next expanded part or rib 42 inthat the mutilated gear 34 will again enter into mesh with the bevel gear 33. By way of example a seamless tubular section is indicated by the dotted lines 100 in Figure G and .said showing is intended to illustrate the initial radial dellection of the outer end of a pipe after the first creasing is effected. Obviously, the machine will operate in identical manner upon seamed tubular sections as the bar 84 effectively prevents any upward bulging in either case, and it will be clearly apparent that by my invention there is provided an elbow making machine that will rapidly produce yhighly finished elbows from straight tubular sections in afminimum of time with a consequential increased output and the saving of much time and labor.

Whilst there has been shown and minutely described a preferred embodiment of my invention it is to be clearly understood that many detail changes and variations can be effected without departing from the essential features as hereinbefore set forth, and the right is hereby reserved to make all such reasonable modifications thereof as fairly fall within the scope of the appended claims.

Having described my invention, what I claim as new and desire to secure by Letters Patent is: i

l. In an elbow making Amachine the combination with a base having spaced bearings, a tubular mandrel having plugged ends securely mounted in one of the bearings and having its free end concentric within the bore of the other bearing the outer side whereof is eccentrically flared, a shaft eccentrically journaled in the plugged ends of the tubular mandrel and having a longitudinally projecting crank pin, an annular clamping die, abutting forming-disks operable by the crank pin and fulcrumed between the end of said mandrel and said annular clamping die, a creasing'die hingedly mounted concentrically over the clamping die, means for intermittently preventing movement of the creasing die, and means for Laagste l j ournaledv within an'diiny parallel relation to the amis of thetubular mandrel, said shaft having a crank pin projecting from its outer end, an annularV 'clamping die7 abutting forming-disks operable by the crank pin and fulcrumed between the end of said mandrel and said annular clamping die, ak creasing die hingedly mounted concentrically over the clamping die, means for intermittently preventing movement of the creasing die, and meansv for feeding a tubular section from ofi' the mandrel after the creasing die is released and returned.

1n an elbow making machine the combination with a base having spaced bearings, a tubular mandrel securely mounted in one of the bearings and having its free end concentric within the other bearing, the outer side wherof is eccentrically flared, a shaft journaled within and iny parallel relation to the axis of the tubular mandrel, said shaft having a crank pin projecting from its outer end, an annular clamping die overlying` forming-disks operable by the crank piny and fulcrumed between the' outer end of said mandrel and said annular clamping die, one of said formingdisks having` an oscillatory and the other an eccentric peripheral movement relative to their common fulcrum,v a creasing die hingedly mounted concentrically over the clamping die, means for intermittently preventing movement of the creasing die, andl means for feeding a tubular section from off the mandrel after the creasing die is released and returned.

l. 1n an elbow making machine the com bination with a Vbase having 'spaced bearings7 a tubular mandrel securely mounted in one of theA bearings andy having its free end concentric within the other bearing, the outer side whereof is eccentrically flared, a shaft journaled within and in parallel relation to the axis of the tubular mandrel., an annular clamping die, said shaft having aora-nk pin projecting from its outer end, overlying forming-disks operable by the crank pin and fulcrumed between the outer end of .said mandrell and` said annular clamping die,- one of said forming-disks having an oscillatory and the other an eccentric peripheral movement relative Yto their common fulcrum, the eccentrically moving forming-disk having diametrically aligning slots to permit of its eccentric movement, a creasing die hingedly mounted concentricallv over the clamping die(- meansyfor intermittently preventing movementiof the creas-ingdie. vandmeans' for feeding, a tubular section from off the mandrel after the creasing die is released and returned.

v5'. 1n an elbow making machine the, com bination with a base having spaced bearings, a= tubular mandrelsecurely mount-ed in one of the bearings and-having its iree end coneif centric within the: other bearing the kouter relative to their common fulcrum, means for limiting the oscillatory and eccentric peripheral travel of the forming-disks over the end of the tubular mandrel, a creasing die hingedly mounted concentrically over the clamping die, means for intermittently preventing movement of the creasing die, and means for feeding a tubular section from off the mandrel after the creasing die isreleased and returned.

6. 1n an elbow makingfmachinethe combination with a base having spaced bearings, a tubular mandrel securely mounted in one of the bearings and having its free end concentric within the other bearing", the outer side whereof is eccentrically flared, a shaft j ournaled within and: in parallel relation to the aXis ofy the tubulanmandrel, said shaft having a crank pin proj ectingr from itsouter end, an annular clamping die, overlying forming-disks operable by the crank. pin and fulcrumed between the outer end of said mandrelv and said annular clamping die fashioned with a rounded lower frontal part, one of said forming-disks having. an oscillatory and the other an eccentric peripheral movement relative to their` common fulcrum,

means for limiting the oscillatory and eccen` tric peripheral travel of the forming-disks over the end of the tubular mandrel', a creas-V ing die hingedly mounted' ooncentrically over the clamping die, means for intermittently preventing movement of the creasing die? and means for feeding a tubular section fromoff the mandrel after'the creasing die is released and returned.

7. In an elbow making machine the combination with a base having spaced bearings, a tubular mandrel securely mounted in one of the bearings and having its freeend concentric withi-n the other bearing,` the outer side whereof is eccentrically flared7 a shaft jonrnaled within. and in parallel relation tothe axis of the tubular mandrel, said shaft having a crank pin projecting from its outer end, an. annular clamping die, overL lyingl forming-disks operable by the crank pin and fulcrumed between the outer end of said mandrel and said annular clamping die fashioned with a. roundedy lower frontal part, one of said forming-disksA having an oscillatory and the other an eccentric peripheral movement relative to their common fulcrum, means for limiting the oscillatory. andV eccentric peripheraltravel of the formiing-disks over the end of the tubular manN drei, a. hinged creasing` die concentricl with the clamping die andfhaving an eccentric flaring opposed to the aforesaid flared bearing, an internal arcuate bead within the creasing die and a concave outlet therefrom, means for intermittently preventing movement of the creasing die, and means for feeding a tubular section from off the man' drel after the creasing die is released and returned.

8. In an elbow making machine the combination with a base having spaced bearings, a tubular mandrel securely mounted in one of the bearings and having its free end concentric within the other bea-ring, the outer side whereof is eccentrically flared. a shaft journaled within and in parallel relation to the aXis of the tubular mandrel, said shaft having a crank pin projecting from its outer end, an annular clamping die,'over lying forming-disks operable by the crank pin and fulcrumed between the outer end of said mandrel and said annular clamping die fashioned with a rounded lower frontal part, one of said forming-disks having an oscillatory and the other an eccentric peripheral movement relative to their common fulcrum, means for limiting` the oscilla-tory and eccentric peripheral travel of the forming-disks over the end of the tubular mandrelr` a hinged creasing` die concentric with the yclamping die and having an eccentric flaring opposed to the aforesaid flared bear ing, an internal arcuate bead within the creasing-die and a concave outlet therefron'n an internal cam, alocking lever operable by said .internal cam for intermittently preventing movement of the creasing die, and means for feeding a tubular section from off the mandrel after the creasing die is released and returned.

9. In an elbow making machine the combination with a base having spaced bearings, a tubular mandrel securely mounted in one of the bearings and having its free end concentric within the other bearing, the outer side whereof is eccentrically flared, a shaft journaled within and in parallelrelation to the axis of the tubular mandrel, said shaft having a crank pin projecting from its outer end, an annular clamping die. overlying forming-disks operable by the crank pin and fulcrumed between the outerend of said mandrel and said annular clamping die fashioned with a rounded lower part, one of said forming-disks havingan oscillatory and the other an eccentric pe ripheral movement relative to their common fulcrum, means lfor limiting the oscillator and eccentric peripheral travel of the forming-disks over the end of the tubular mandrel, a hinged creasing' die concentric with the clamping dieV and having an eccentric flaring opposed to the aforesaid flared bearfronta-l c ing, an internal arcuate bead within the creasing die and a concave outlet therefrom, an internal caniA` a locking lever operable by said internal. cam for intermittently prcventing` movement of thc creasing die, a thrust collar movable longitudinally of the tubular mandrel and having an annular groove for feeding the end of a tubular soction to be elbowed, and means for forcing the thrust collar forward step by step after each release and return of the creasing die.4

l0; In an elbow making machine the combination with a base having spaced bearings,` a tubular mandrel securely mounted in one of the bearings and having its free end concentric within the other bearing, the outer side whereof is eccentrically flared, a shaft journaled within and in parallel relation to the axis of the tubular mandrel, said shaft having a crank pin projecting from its outer end, an annular clamping die, overlying forming-disks operable by the crank pin and fulorumed between the outer end of said mandrel and said annular clamping die fashioned with a rounded lower frontal part, one of said forming-disks having an oscillatory and the other an eccentric peripheral travel vover the end of the tubular mandrel, a hinged creasing die concentric with the clamping die and having` an eccentric flaring opposed to the aforesaid liared bearing, an internal arcuate bead within the creasing die and a concave outlet therefrom, an internal ca i, a locking lever operable by said internal cam for intermittently preventing increment of the creasing die, 'a thrust collar movable longitudinally of the tubular mandrel and having an annular groove for feeding the end of a tubular section to be elbowed, a toothed rack bar carried by said thrust collar` a pivoted yoke straddling the rack bar and having a gravity fall pawl engaging the teeth thereof, and means for movingl said rack ba r forwardly step by step after each release and return of the thrust collar.

1l. In an elbow makingmachine the combination with a base having spaced bearings, a tubular mandrel securely mounted in one of the bearings and havin;r its free end concentric within the other bearing. the outer side whereof is eccentricall;v flared, shaft journaled within yand in parallel relation to the axis of the tubular mandrel, said shaft having a crank; pin projecting from its outer end. an rannular clamping die. overlying formingdisks operable by the crank pin and fulcrumed between the outer end of said mandrel and said annular clamping die fashioned with a rounded lower frontal. part, one of said forming-disks having an oscillatory and the other an eccentric peripheral travel over the end of the tubular mandrel, a hinged creasing die concentric with the clamping die and having an eccentric flaring opposed to the aforesaid flared bearing, an

internal arcuate bead within the creasing die and a concave outlet therefrom, an internal camy a locking lever operable by said intei`` nal cam for intermittently preventing iiiovenient of the creasing die, a thrust collar movable longitudinally of the 4tubular mandrel and having an annular groove for feeding the end ofv a. tubular section to be elbowed, a toothed rack bar carried by said thrust collar, a pivoted yoke straddlingthe rack bar r and having a gravity fall pawl engaging the teeth thereof, and strap eccentrics for rocking the pivoted yoke to effect the intermittent feeding forward of the thrust collar after each release and return of the creasing die. i 4

l2. ln an elbow making machine the combination .with a base having spaced bearings, a tubular mandrel securely mounted in one of the bearings and having its free end concentric within the other bearing, the outer side whereof is eccentrically flared, a shaft j ournaled within and in parallel relation to the axis of the tubular mandrel, said 'shaft having` a crank pin projecting from its outer end, an annular clamping die, overlying forming-disks operable bythe crank pin and fulcriuned between the youter end of said mandrel and said annular clamping die fashioned with a rounded lower frontal part, one

- of said forming-disks having an oscillatory and the other an eccentric peripheral travel over the end of the ,tubular mandrel, a hinged creasing die concentric with the clamping die and having an eccentric flaring opposed to the aforesaid flared bearing, an internal arcuate bead within the creasing die and a concave outlet therefrom, a locking lever operable by an internal cam for intermittently preventing movement of the creasing die, a thrust colla-r movable longitudinally of the tubular mandrel and having an annular groove for feeding the end of a tubular section to be elbowedy a toothed rack bar carried by said thrust collar, a pivoted yoke straddling the rack bar and having a gravity fall pawl engaging the teeth thereof, and means for preventing the bulging` of the tubular section during the creasing oper-l ation.

13. In an elbow making machine conipiisi inpabase having bearings, a mandrel supimrted by one of said bearings, a shaft jouriialcd loi tudinally in said mandrel and having a project' f crank pin at its free ineansffor intermittently rotatingr said shan., :i hinged formino' and creasing die at the outer end of said mandrel, abutting forming-disks operable by the crank pin and fulcruined on the end of said nnindreln thecoinbination of an annular clamping die,

said die being fashioned with a lower frontal part andan eccentrically disposed aperture therein to permit. the rotation of the aforeable by the crank pin and fulcruined between the outer end Aof said mandrel and saidr annular clamping die vfashioned with a rounded lower frontal part, kone of rsaid formingdisks having anfoscillatory'and the other an eccentric peripheral travel over the 4end of the tubular inandreh` `hinged creasing die concentric with the clamping die and having an eccentric flaring opposed to the aforesaid flared bearing, an internal arcuate rbead within ythe creasing die land a concave outlet therefrom, an internal camj a locking lever operable by said internal cam for intermit-- tently preventing movement of the creasing die, a thrust collar movable longitudinally. of the tubular mandrelv and having an annular groove for feeding` the ond of a tiif bulai' section to be elbowed, a .toothed rack y bar carried by said thrust collar, a pivoted yoke straddling the rack bar and having` a gravity fall pawl engaging the teeth thereof, and means for preventing the bulging` of the tubular section during the creasing operation. i A

In testimony whereof l aflix niv signature.

` AUGUST D. KUMPF.

ico 

